1. Field of the Invention
This invention relates to an optical connector and the structure of an optical connector-packaging/mounting portion used in the field of optical communication such as an OA, an FA and equipments mounted on a car.
2. Description of the Related Art
In the type of optical connector to be fixedly mounted on a packaging board, with an optical element contained therein, there has heretofore been adopted a construction in which the optical element is received in a shield casing of metal for noise protection purposes, and this casing is received in a housing made of a resin.
In the above conventional optical connector, however, a small gap existed between the shield casing and a packaging surface of the packaging board, and therefore there was a possibility that noises intruded to the optical element from the exterior through this gap. This problem becomes conspicuous particularly in a higher-frequency operation.
And besides, the optical element, which is a heat-generating element, is mounted within the resin-molded housing, and therefore heat, generated by the optical element, can not be efficiently radiated to the exterior, and the temperature of the optical element rises, so that a use environment temperature condition becomes severe.
Therefore, a first object of this invention is to provide an optical connector and a structure of an optical connector-packaging/mounting portion which are excellent in noise resistance, and a second object is to provide an optical connector and the structure of an optical connector-packaging/mounting portion which are excellent in heat-radiating ability.
In order to achieve the first object, according to a first aspect of the invention, there is provided an optical connector for being mounted on and fixed to a packaging board, which optical connector comprises a shield casing made of an electrically-conductive material, an element body portion of an optical element being able to be inserted into the shield casing through an opening, formed in a bottom thereof, to be received therein; and a connector housing member which can be mounted on and fixed to the packaging board; wherein the shield casing is received in the connector housing member in such a manner that when the connector housing member is mounted on and fixed to the packaging board, at least a peripheral edge portion of the opening, formed in the bottom of the shield casing, can be contacted with a packaging surface of the packaging board.
In order to achieve the second object, according to a second aspect of the invention, the shield casing may include a radiating portion which is exposed to the exterior of the connector housing member so as to radiate heat, generated by the optical element, to the exterior.
According to a third aspect of the invention, there may be provided shield casing-side screw-fastening piece portions which are formed on and project from the shield casing, and can be screw-fastened to the packaging board in such a manner that the screw-fastening piece portions are held in contact with a grounding-purpose wiring pattern formed on the packaging surface of the packaging board.
According to a fourth aspect of the invention, there may be provided housing-side screw-fastening piece portions which are formed on and project from the connector housing member, and can be screw-fastened, together with the shield casing-side screw-fastening piece portions, to the packaging board in superposed relation to the respective shield casing-side screw-fastening piece portions.
According to a fifth aspect of the invention, the shield casing may have a soldering surface which can be soldered to the grounding-purpose wiring pattern, formed on the packaging surface of the packaging board, when the connector housing member is mounted on and fixed to the packaging board.
According to a sixth aspect of the invention, there is provided a structure of an optical connector-packaging/mounting portion, which comprises an optical connector comprising a shield casing made of an electrically-conductive material, an element body portion of an optical element being able to be inserted into the shield casing through an opening, formed in a bottom thereof, to be received therein; and a connector housing member in which the shield casing is received in such a manner that a bottom of the connector housing is exposed to the exterior; and a packaging board on which the optical connector is mounted on and fixed to; wherein the connector housing member is mounted on and fixed to the packaging board in such a manner that at least a peripheral edge portion of the opening, formed in the bottom of the shield casing, is contacted with a packaging surface of the packaging board.
According to a seventh aspect of the invention, a grounding-purpose wiring pattern may be formed on the packaging surface of the packaging board over an area including that portion thereof with which the bottom of the shield casing is contacted when the optical connector is mounted on and fixed to the packaging board.
According to an eighth aspect of the invention, there may be provided shield casing-side screw-fastening piece portions which are formed on and project from the shield casing, and the shield casing-side screw-fastening piece portions are screw-fastened to the packaging board in such a manner that the screw-fastening piece portions are held in contact with the grounding-purpose wiring pattern formed on the packaging surface of the packaging board.
According to a ninth aspect of the invention, the shield casing may be soldered to the grounding-purpose wiring pattern formed on the packaging surface of the packaging board.